BQ40Z50-R1: Derating use battery capacity for extend battery cycle life

Dears,

     cell spec : 3~4.2V

     battery structure: 3s1p

     We want to extend battery cycle life.  So just charge battery to 4V and discharge to 3.2V. We need SOC is 100% at 4V and 0% at 3.2V.

•  For GPCCHEM data collect we charge single cell battery to 4.2V and relax 2h then discharge to 3V then relax 5h.

Is it right? Or I need charge to 4V and discharge to 3.1V?

•  I just set FC voltage threshold to 4V、Design voltage to 12V、Term Voltage to 9.6V in bq40z50-R1.

    My question is if the IT gauge suit for this application? Or CEDV is better?

 Because I think Ra table algorithm is base on SOC,and  in this application the SOC is not real battery SOC.

And SOC is base on OCV table. If only charge to 4V and bq40z50-R1 look up OCV table will never reach 100% SOC.

Thanks!